Document Type : Original Article

Authors

Ethiopian Environment and Forest Research Institute, Forest Products Innovation Research and Training Center, Addis Ababa, Ethiopia.

Abstract

The low bulk density of wood wastes causes handling, storage, and transportation issues, limiting its large-scale application. Pelletization can solve this inherent problem by converting biomass into dense and compact pellets with regular shape and size. To evaluate the effect of particle size and binding agents on pellets of carbonized Pinus patula sawdust, the particle size of 0.6 mm, 1.18 mm and 2.3 mm and binding agents of cow dung, molasses and wastepaper were used. The experimental results indicated that the addition of cow dung and molasses into the carbonized sawdust resulted in increase of calorific value, decrease of ash content and increase of fixed carbon. As a result, the maximum calorific value of 28.47 MJ/kg, ash content of 2.93%, and fixed carbon of 59.32% were obtained by using molasses.The calorific value of 25.8 MJ/kg, ash content of 6.03% and fixed carbon of 52.77% were obtained by using cow dung. Whereas, addition of wastepaper into carbonized sawdust resulted in lower calorific value of 22.3 MJ/kg, highest ash value of 8.35% and low fixed carbon of 43.2%. Therefore, the use of cow dung and molasses as a binder can be considered as a sustainable approach to improve the physicochemical properties of biomass pellets.

Keywords

Main Subjects

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